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a\left(-2\right)a-2\times 3a^{2}=4a
Variable a cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4a, the least common multiple of 4,-2a.
a^{2}\left(-2\right)-2\times 3a^{2}=4a
Multiply a and a to get a^{2}.
a^{2}\left(-2\right)-6a^{2}=4a
Multiply -2 and 3 to get -6.
-8a^{2}=4a
Combine a^{2}\left(-2\right) and -6a^{2} to get -8a^{2}.
-8a^{2}-4a=0
Subtract 4a from both sides.
a\left(-8a-4\right)=0
Factor out a.
a=0 a=-\frac{1}{2}
To find equation solutions, solve a=0 and -8a-4=0.
a=-\frac{1}{2}
Variable a cannot be equal to 0.
a\left(-2\right)a-2\times 3a^{2}=4a
Variable a cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4a, the least common multiple of 4,-2a.
a^{2}\left(-2\right)-2\times 3a^{2}=4a
Multiply a and a to get a^{2}.
a^{2}\left(-2\right)-6a^{2}=4a
Multiply -2 and 3 to get -6.
-8a^{2}=4a
Combine a^{2}\left(-2\right) and -6a^{2} to get -8a^{2}.
-8a^{2}-4a=0
Subtract 4a from both sides.
a=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}}}{2\left(-8\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -8 for a, -4 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{-\left(-4\right)±4}{2\left(-8\right)}
Take the square root of \left(-4\right)^{2}.
a=\frac{4±4}{2\left(-8\right)}
The opposite of -4 is 4.
a=\frac{4±4}{-16}
Multiply 2 times -8.
a=\frac{8}{-16}
Now solve the equation a=\frac{4±4}{-16} when ± is plus. Add 4 to 4.
a=-\frac{1}{2}
Reduce the fraction \frac{8}{-16} to lowest terms by extracting and canceling out 8.
a=\frac{0}{-16}
Now solve the equation a=\frac{4±4}{-16} when ± is minus. Subtract 4 from 4.
a=0
Divide 0 by -16.
a=-\frac{1}{2} a=0
The equation is now solved.
a=-\frac{1}{2}
Variable a cannot be equal to 0.
a\left(-2\right)a-2\times 3a^{2}=4a
Variable a cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4a, the least common multiple of 4,-2a.
a^{2}\left(-2\right)-2\times 3a^{2}=4a
Multiply a and a to get a^{2}.
a^{2}\left(-2\right)-6a^{2}=4a
Multiply -2 and 3 to get -6.
-8a^{2}=4a
Combine a^{2}\left(-2\right) and -6a^{2} to get -8a^{2}.
-8a^{2}-4a=0
Subtract 4a from both sides.
\frac{-8a^{2}-4a}{-8}=\frac{0}{-8}
Divide both sides by -8.
a^{2}+\left(-\frac{4}{-8}\right)a=\frac{0}{-8}
Dividing by -8 undoes the multiplication by -8.
a^{2}+\frac{1}{2}a=\frac{0}{-8}
Reduce the fraction \frac{-4}{-8} to lowest terms by extracting and canceling out 4.
a^{2}+\frac{1}{2}a=0
Divide 0 by -8.
a^{2}+\frac{1}{2}a+\left(\frac{1}{4}\right)^{2}=\left(\frac{1}{4}\right)^{2}
Divide \frac{1}{2}, the coefficient of the x term, by 2 to get \frac{1}{4}. Then add the square of \frac{1}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
a^{2}+\frac{1}{2}a+\frac{1}{16}=\frac{1}{16}
Square \frac{1}{4} by squaring both the numerator and the denominator of the fraction.
\left(a+\frac{1}{4}\right)^{2}=\frac{1}{16}
Factor a^{2}+\frac{1}{2}a+\frac{1}{16}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(a+\frac{1}{4}\right)^{2}}=\sqrt{\frac{1}{16}}
Take the square root of both sides of the equation.
a+\frac{1}{4}=\frac{1}{4} a+\frac{1}{4}=-\frac{1}{4}
Simplify.
a=0 a=-\frac{1}{2}
Subtract \frac{1}{4} from both sides of the equation.
a=-\frac{1}{2}
Variable a cannot be equal to 0.